Shoe with lattice structure

ABSTRACT

An article of footwear includes an upper, a midsole connected to the upper, and an outsole connected to the midsole. The midsole includes a platform extending along a perimeter portion of the midsole and a lattice structure integrally formed with the platform, the lattice structure including a network of laths.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent document is a continuation of and claims priority from U.S.patent application Ser. No. 15/067,250, filed Mar. 11, 2016, which is acontinuation of and claims priority from U.S. patent application Ser.No. 13/829,624, filed Mar. 14, 2013, the contents of which areincorporated herein by reference in their entirety.

FIELD

This disclosure relates generally to shoes and specifically to supportarrangements for shoe soles, and methods of making the same.

BACKGROUND

FIG. 1 shows a shoe 10 to be worn on a foot of a user with a portion ofthe shoe 10 cut away so that the inside of the shoe 10 is partiallyvisible. The shoe 10 includes an upper 14 and a sole 18 coupled to theupper 14. The upper 14 covers the top and sides of the user's foot, andthe sole 18 covers the bottom of the user's foot and makes contact withthe ground. The sole 18 typically includes an insole 22, a midsole 26,and an outsole 30 which cushion and protect the user's foot while theuser makes contact with the ground. The insole 22 contacts the user'sfoot, the outsole 30 contacts the ground, and the midsole 26 is arrangedbetween the insole 22 and the outsole 30. The insole 22 generallyprovides a comfortable surface for contact with the user's foot and istypically essentially comprised of a thin layer of a man-made materialsuch as, for example, ethylene vinyl acetate. The midsole 26 generallyprovides most of the cushioning and shock absorption for the foot of theuser and is typically essentially comprised of a polymer such as, forexample, polyurethane, surrounding another material such as, forexample, a foam, a gel, or capsules filled with air. The outsole 30generally provides a durable surface which can sustain repeated impactand friction with the ground and is typically essentially comprised of arubber such as, for example, carbon rubber or blown rubber.

The sole 18 includes a heel end 34 arranged where a user's heel ispositioned when wearing the shoe 10 and a toe end 38 arranged oppositethe heel end 34 where the user's toes are positioned when wearing theshoe 10. The sole 18 also includes a medial side 42 arranged closest tothe user's center of symmetry when wearing the shoe 10 and a lateralside 46 arranged opposite the medial side 42 farther from the user'scenter of symmetry when wearing the shoe 10.

Turning now to FIG. 2 and FIG. 3, schematic drawings of a user's foot 50are shown including a heel 54, toes 56, an arch 58, a medial side 60,and a lateral side 62. FIG. 2 depicts a perspective lateral side view ofthe bone structure of the foot 50, and FIG. 3 depicts a bottom view ofthe foot 50 including a plurality of regions located relative to theheel 54, toes 56, arch 58, medial side 60, and lateral side 62. Acalcaneus region 66 (shown in FIG. 3) on the bottom of the foot 50 islocated substantially beneath a calcaneus bone 68 (shown in FIG. 2) ofthe user, near the heel 54. A talus region 70 (shown in FIG. 3) on thebottom of the foot 50 is located substantially beneath a talus bone 72(shown in FIG. 2) of the user, between the heel 54 and the arch 58. Alongitudinal arch region 74 (shown in FIG. 3) on the bottom of the foot50 is located substantially beneath a navicular bone 76, a cuboid bone78 and cuneiform bones 80 (shown in FIG. 2) of the user, near the arch58. A metatarsal region 82 (shown in FIG. 3) on the bottom of the foot50 is located substantially beneath metatarsal bones 84 (shown in FIG.2) of the user, between the arch 58 and the toes 56. A ball of the footregion 86 (shown in FIG. 3) on the bottom of the foot 50 is locatedsubstantially beneath the metatarsal-phalangeal joints 88 and sesamoids90 (shown in FIG. 2) of the user, between the arch 58 and the toes 56and closer to the medial side 60 than the lateral side 62. A toe region92 (shown in FIG. 3) on the bottom of the foot 50 is locatedsubstantially beneath phalangeal bones 94 (shown in FIG. 2) of the user,near the toes 56.

When propelling himself on his feet, the user applies different amountsof pressure at different times to the various bones in each foot 50during what is known as a gait cycle. For example, during a typicalwalking motion, the gait cycle begins when the user first contacts theground with the heel 54 of his foot 50, thereby applying pressure to thecalcaneus bone 68. As the user shifts his weight forward on his foot 50,he applies less pressure to the calcaneus bone 68 and begins to applypressure to the talus bone 72, the navicular bone 76, the cuboid bone78, and the cuneiform bones 80. As the user begins to propel himself offhis foot 50, he applies less pressure to the talus bone 72, thenavicular bone 76, the cuboid bone 78, and the cuneiform bones 80 andbegins to apply pressure to the metatarsal bones 84. As the user propelshimself forward, he applies pressure along the metatarsal bones 84 andto the metatarsal-phalangeal joints 88 and sesamoids 90. Finally, as theuser begins to toe off and end contact with the ground, he applies lesspressure to the metatarsal-phalangeal joints 88 and sesamoids 90 andapplies pressure to the phalangeal bones 94. Finally, to toe off, theuser applies pressure to the phalangeal bones 94 to propel forward. Theuser then lifts his foot 50 into a leg swing, and places it down in alocation forward relative to where he lifted it. When the user placeshis foot 50 down again, he first contacts the ground with the heel 54,beginning a new cycle of the walking motion.

Many styles of forward propulsion, including many styles of walking andrunning, apply a gait cycle substantially similar to that describedabove. In some styles of forward propulsion, such as, for example,sprinting or shuffling, different amounts of pressure are applied todifferent portions of the foot 50 for different amounts of time.Additionally, the particular amounts of pressure applied to differentportions of the foot 50 can vary from one individual to another. Forexample, some individuals apply more pressure to the medial side 60 thanthe lateral side 62 as they progress through the gait cycle. Thisparticular application of pressure is known as pronation. In contrast,some individuals apply more pressure to the lateral side 62 than themedial side 60 as they progress through the gait cycle. This particularapplication of pressure is known as supination. Additionally, someindividuals apply more pressure to their heels 54 when contacting theground and some contact the ground with a portion of their feet nearerto the arch 58.

Shoes are designed to support and protect the feet of users during gaitcycles to provide comfort and to promote efficient propulsion. However,due to differences between individuals in both foot anatomy and personalgait cycle style, some shoes are more comfortable and useful for someusers than others. Additionally, producing a shoe configured to meet thevariety of needs during all stages of the gait cycle can includeproducing a large number of different specialized parts which must beassembled into the shoe. Production and assembly of parts arecontributing factors to the cost of the shoe. In general, a shoe havinga larger number of parts is more expensive to produce than a shoe havinga smaller number of parts. In view of the foregoing, it would beadvantageous to provide a shoe that is comfortable and useful for a userand that is inexpensive to produce. It would also be advantageous toprovide a shoe with a support arrangement that can be easily customizedto meet the unique needs of various foot anatomies and individual gaitstyles.

SUMMARY

In accordance with one exemplary embodiment of the disclosure, there isprovided an article of footwear comprising an upper, a midsole connectedto the upper, and an outsole connected to the midsole. The midsoleincludes a platform extending along a perimeter portion of the midsoleand a lattice structure integrally formed with the platform, the latticestructure including a network of laths.

In accordance with another exemplary embodiment of the disclosure, thereis provided an article of footwear comprising an upper, a midsoleconnected to the upper, and an outsole connected to the midsole. Themidsole comprises a lattice structure including a network of lathsforming a plurality of cell units. The plurality of cell units includecomplete cell units and incomplete cell units.

In accordance with yet another exemplary embodiment of the disclosure,there is provided an article of footwear comprising an upper, a midsoleconnected to the upper, and an outsole connected to the midsole. Themidsole includes a lattice structure including a network of lathsforming a plurality of octahedron cell units.

The above described features and advantages, as well as others, willbecome more readily apparent to those of ordinary skill in the art byreference to the following detailed description and accompanyingdrawings. While it would be desirable to provide an article of footwear,a midsole or a method of making an article of footwear that provides oneor more of the advantageous features, the teachings disclosed hereinextend to those embodiments which fall within the scope of the appendedclaims, regardless of whether they accomplish one or more of theabove-mentioned advantages.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic drawing of a shoe as is generally known in theprior art.

FIG. 2 is a schematic drawing of a medial side view of a bone structureof a foot.

FIG. 3 is a schematic drawing of a bottom view of a foot.

FIG. 4 is a bottom perspective view of a midsole including a platformand a lattice structure.

FIG. 5 is a top view of the midsole of FIG. 4.

FIG. 6 is a schematic drawing of a lath of the lattice structure of FIG.4.

FIG. 7 is a schematic drawing of a cell unit of the lattice structure ofFIG. 4.

FIG. 8 is a bottom view of the midsole of FIG. 4.

FIG. 9A is a schematic drawing of a first portion portions of thelattice of FIG. 4 with partial or incomplete laths or vertices;

FIG. 9B is a schematic drawing of a second portion of the lattice ofFIG. 4 with partial or incomplete laths or vertices;

FIG. 9C is a schematic drawing of a third portion of the lattice of FIG.4 with partial

or incomplete laths or vertices.

FIG. 10 is a bottom view of the midsole of FIG. 4 positioned within anoutsole.

FIG. 11 is a flowchart depicting a process for forming the midsole ofFIG. 4.

FIG. 12 is a flowchart depicting another process for forming the midsoleof FIG. 4.

DETAILED DESCRIPTION

As shown in FIG. 4, a midsole 100 includes a platform 104 and a latticestructure or lattice 108. The platform 104 includes a first surface 112and a second surface 116 opposite the first surface 112. The firstsurface 112 is configured to be oriented toward a bottom of the foot 50(shown in FIGS. 2 and 3) of a user when the user is wearing a shoe, suchas, for example, the shoe 10 shown in FIG. 1, including the midsole 100.The second surface 116 is configured to be oriented away from the bottomof the foot 50 (shown in FIGS. 2 and 3) of the user when the user iswearing a shoe, such as, for example, the shoe 10 shown in FIG. 1,including the midsole 100. The lattice 108 is integrally formed with thesecond surface 116 of the platform 104 and covers substantially all ofthe second surface 116 of the platform 104. As used herein, the phrase“integrally formed with” is intended to mean formed together of the samematerial so as to be inseparable parts of a whole. The platform 104 andlattice 108 are essentially comprised of, for example, a polymer suchas, for example, nylon.

With reference to FIG. 5, the platform 104 also includes contours 118formed on the first surface 112 and configured to match contours of asurface of the bottom of the foot 50 (shown in FIGS. 2 and 3) of theuser. The contours 118 are substantially shaped as topographic ridgesformed as discreet and distinct raised levels from the first surface 112of the platform 104. By matching the contours 118 of the surface of thebottom of the foot 50 (shown in FIGS. 2 and 3) of the user, the platform104 is configured to receive the foot 50 (shown in FIGS. 2 and 3) in amanner that feels natural to the user and that provides enhanced supportand comfort to the user.

The platform 104 also includes a heel end or heel portion 120, a toe endor toe portion 124, an arch side or medial portion 128, and an outwardside or lateral portion 132. The platform 104 is configured such thatwhen the midsole 100 is included in a shoe, such as, for example, theshoe 10 shown in FIG. 1, the heel portion 120 is positionedsubstantially above the heel end 34 of the sole 18 (shown in FIG. 1),the toe portion 124 is positioned substantially above the toe end 38 ofthe sole 18 (shown in FIG. 1), the medial portion 128 is positionedsubstantially above the medial side 42 of the sole 18 (shown in FIG. 1),and the lateral portion 132 is positioned substantially above thelateral side 46 of the sole 18 (shown in FIG. 1). Accordingly, when auser is wearing the shoe including the midsole 100, the heel portion 120is arranged to support the heel 54 of the foot 50 (shown in FIGS. 2 and3), the toe portion 124 is arranged to support the toes 56 of the foot50 (shown in FIGS. 2 and 3), the medial portion 128 is arranged tosupport the medial side 60 of the foot 50 (shown in FIGS. 2 and 3), andthe lateral portion 132 is arranged to support the lateral side 62 ofthe foot 50 (shown in FIGS. 2 and 3).

Returning now to FIG. 4, the lattice 108 extends generally outwardlyfrom the second surface 116 of the platform 104. The lattice 108includes a plurality of laths 136. For clarity, FIG. 6 shows a schematicdrawing of one lath 136 of the plurality of laths 136. The lath 136 hasa substantially longitudinal structure including a longitudinal axis140, a first end 144, and a second end 148. In the exemplary embodimentof FIG. 6, the lath 136 is substantially cylindrical in shape. The lath136 also has a length 150 and a girth 152 that is centered about thelongitudinal axis 140 and extends substantially uniformly from the firstend 144 to the second end 148. The girth 152 is a measure ofcircumference of the lath 136. Because the lath is substantiallycylindrically shaped, the girth 152 can be calculated with the radius Rmeasured from the longitudinal axis 140 to the edge of the lath 136 in adirection perpendicular to the lath 136. The girth 152 of the lath isequal to 2×π×R. In at least one exemplary embodiment, the length 150 ofthe lath 136 is approximately 9 millimeters.

With continued reference to FIG. 4, the lattice 108 also includes aplurality of cell units 156. For clarity, FIG. 7 shows a schematicdrawing of eight views of one cell unit 156 of the plurality of cellunits 156. The cell unit 156 is substantially shaped as an octahedronand is defined by eight faces 160A-160H, six vertices 164A-164F, andeight laths 136A-136H. Each of the faces 160A-160H is substantiallyshaped as an equilateral triangle. An octahedron has a volume determinedby the length of each side. Accordingly, the volume of the cell unit 156is determined by the length 150 of each lath. In at least one exemplaryembodiment, each lath 136A-136H has a length of approximately 9millimeters such that the cell unit 156 has a volume of approximately0.34 centimeters cubed. So that the volume of the cell unit 156 is notaltered by the girth 152 (shown in FIG. 6) of each lath 136A-136H, thevolume of the cell unit 156 is measured within the boundary defined bythe longitudinal axis 140 (shown in FIG. 6) of each lath 136A-136H.

With continued reference to FIG. 7, each of the six vertices 164A-164Fis formed by the intersection or joining together of the first end 144or the second end 148 (shown in FIG. 6) of at least two of the laths136A-136H. More specifically, vertex 164A is formed by the intersectionof an end of four laths: 136A, 136B, 136C and 136D. Vertex 164B isformed by the intersection of an end of two laths: 136A and 136E. Vertex164C is formed by the intersection of an end of two laths: 136B and136F. Vertex 164D is formed by the intersection of an end of two laths:136C and 136G. Vertex 164E is formed by the intersection of an end oftwo laths: 136D and 136H. Finally, vertex 164F is formed by theintersection of an end of four laths: 136E, 136F, 136G and 136H.

Each of the faces 160A-160H is defined by an area, bound by two laths ofthe laths 136A-136H, within a plane defined by three adjacent verticesof the vertices 164A-164F. More specifically, the face 160A is an area,bound by laths 136C and 136D, within the plane defined by adjacentvertices 164A, 164D and 164E. The face 160B is an area, bound by laths136A and 136C, within the plane defined by adjacent vertices 164A, 164Band 164D. The face 160C is an area, bound by laths 136A and 136B, withinthe plane defined by adjacent vertices 164A, 164B and 164C. The face160D is an area, bound by laths 136B and 136D, within the plane definedby adjacent vertices 164A, 164C and 164E. The face 160E is an area,bound by laths 136G and 136H, within the plane defined by adjacentvertices 164D, 164E and 164F. The face 160F is an area, bound by laths136E and 136G, within the plane defined by adjacent vertices 164B, 164Dand 164F. The face 160G is an area, bound by laths 136E and 136F, withinthe plane defined by adjacent vertices 164B, 164C and 164F. Finally, theface 160H is an area, bound by laths 136F and 136H, within the planedefined by adjacent vertices 164C, 164E and 164F.

Returning to FIG. 4, the lattice 108 includes a plurality of cell units156 arranged adjacent to one another and integrally formed with oneanother to construct the lattice 108 as a single unitary part. Thelattice 108 forms a uniform three-dimensional pattern, and adjacent cellunits 156 share laths 136 and/or vertices 164 (shown in FIG. 7) suchthat a single lath 136 can be shared by as many as two adjacent cellunits 156, and a single vertex 164 (shown in FIG. 7) can be shared by asmany as six adjacent cell units 156. Because each cell unit 156 in thepattern is substantially similar, each uniform cell unit 156 in thepattern has a substantially uniform volume.

The lattice 108 extends with a height H from the second surface 116 ofthe platform 104. The height H of the lattice 108 varies along theplatform 104 from the heel portion 120 to the toe portion 124 and fromthe medial portion 128 to the lateral portion 132. For example, as shownin FIG. 4, the height H₁ is different than the height H₂.

As shown in FIG. 8, the platform 104 is shaped to substantially matchthe shape of the bottom of the foot 50 (shown in FIGS. 2 and 3).Accordingly, the platform 104 has an irregular perimeter 172. Becausethe lattice 108 is integrally formed with and covers substantially theentirety of the second surface 116 of the platform 104, the lattice 108is truncated in all directions. In other words, the pattern of thelattice 108 does not extend infinitely in all three dimensions, but islimited by the height H (shown in FIG. 4) and the perimeter 172 and istruncated where it is limited by the height H (shown in FIG. 4) and theperimeter 172. Accordingly, a portion of the plurality of laths 136(shown in FIG. 6), a portion of the plurality of vertices 164 (shown inFIG. 7), and a portion of the plurality of cell units 156 (shown in FIG.7) in the lattice 108 are incompletely formed.

For clarity, FIGS. 9A-9C depict schematic drawings of a number ofincompletely formed parts of the lattice 108. More specifically, asshown in FIG. 9B, by virtue of their position relative to the height Hand abutting the perimeter 172 (shown in FIG. 8), partial or incompletelaths 176 have a length L that is shorter than the length 150 of thefully formed laths 136. Similarly, as shown in FIG. 9C, partial orincomplete vertices 180 are formed by the intersection of fewer laths136 than the four laths 136 which intersect at fully formed vertices 164(shown in FIG. 7). Similarly, partial or incomplete cell units 184 havefewer than eight laths 136 and/or fewer than six vertices 164.Additionally, as shown in FIG. 9A, at least some incomplete cell units184 are formed of incomplete laths 176 and/or incomplete vertices 180.The incomplete laths 176, incomplete vertices 180, and incomplete cellunits 184 are non-uniform with one another but are different as they arepositioned in different locations on the lattice 108 truncated by theperimeter 172 (shown in FIG. 8) and the height H (shown in FIG. 4). Eachincomplete cell unit 184 is defined by at least one vertex 164 orincomplete vertex 180 and at least two laths 136 or incomplete laths176. Accordingly, each incomplete cell unit 184 is defined by at leasttwo partial or incomplete faces 188 defined by an area within a planeformed by at least one vertex 164 or incomplete vertex 180 and bound byat least a portion of two laths 136 or incomplete laths 176.

Returning now to FIG. 8, the lattice 108 includes a plurality of regionsor zones formed along the midsole 100 and positioned relative to theheel portion 120, the toe portion 124, the medial portion 128, and thelateral portion 132. Specifically, the lattice 108 includes a perimeterzone 200, a calcaneus zone 204, a talus zone 208, a longitudinal archzone 212, a metatarsal zone 216, a ball of the foot zone 220, and a toezone 224. Each zone includes complete cell units 156 (shown in FIG. 7)and incomplete cell units 184 (shown in FIGS. 9A-9C), complete laths 136(shown in FIG. 6) and incomplete laths 176 (shown in FIGS. 9A-9C), andcomplete vertices 164 (shown in FIG. 7) and incomplete vertices 180(shown in FIGS. 9A-9C) that are located within that zone of the lattice108. In other words, the term cell unit can be used to refer to acomplete cell unit and an incomplete cell unit, the term lath can beused to refer to a complete lath and an incomplete lath, the term vertexcan be used to refer to a complete vertex and an incomplete vertex, andthe term face can be used to refer to a complete face and an incompleteface.

The perimeter zone 200 is arranged substantially along the perimeter 172of the platform 104 and generally extends approximately 1-20 millimetersinwardly from the perimeter 172. The calcaneus zone 204 is arrangedsubstantially at the heel portion 120 of the platform 104 and issubstantially centered between the medial portion 128 and the lateralportion 132. The talus zone 208 is arranged nearer to the toe portion124 of the platform 104 than the calcaneus zone 204 and is substantiallycentered between the medial portion 128 and the lateral portion 132. Thelongitudinal arch zone 212 is arranged nearer to the toe portion 124 ofthe platform 104 than the talus zone 208 and is substantially spreadacross the medial portion 128 and the lateral portion 132. Themetatarsal zone 216 is arranged nearer to the toe portion 124 of theplatform 104 than the longitudinal arch zone 212 and is substantiallyspread across the medial portion 128 and the lateral portion 132. Theball of the foot zone 220 is arranged nearer to the toe portion 124 ofthe platform 104 than the metatarsal zone 216 and is arranged nearer tothe medial portion 128 than the lateral portion 132. The toe zone 224 isarranged nearer to the toe portion 124 of the platform 104 than the ballof the foot zone 220 and is substantially spread across the medialportion 128 and the lateral portion 132.

The lattice 108 further includes transition areas 228 arranged aroundand between the other zones 200, 204, 208, 212, 216, 220, 224. Thetransition areas 228 include cell units 156 and incomplete cell units184, laths 136 and incomplete laths 176, and vertices 164 and incompletevertices 180 that are not located within any other of the other zones200, 204, 208, 212, 216, 220, 224 of the lattice 108.

The zones 200, 204, 208, 212, 216, 220, 224 are arranged on the lattice108 such that when the midsole 100 is included in a shoe, like the shoe10 shown in FIG. 1, a user's foot 50 (shown in FIGS. 2 and 3) alignswith the midsole 100 and the various zones 200, 204, 208, 212, 216, 220,224 align to support the various regions of the user's foot 50. Morespecifically, when a user wears the shoe 10 including the midsole 100,the bottom of the foot 50 (shown in FIGS. 2 and 3) is generally alignedwithin the perimeter zone 200, the calcaneus region 66 (shown in FIG. 3)generally aligns with the calcaneus zone 204, the talus region 70 (shownin FIG. 3) generally aligns with the talus zone 208, the longitudinalarch region 74 (shown in FIG. 3) generally aligns with the longitudinalarch zone 212, the metatarsal region 82 (shown in FIG. 3) generallyaligns with the metatarsal zone 216, the ball of the foot region 86(shown in FIG. 3) generally aligns with the ball of the foot zone 220,and the toe region 92 (shown in FIG. 3) generally aligns with the toezone 224.

Because the user's foot 50 (shown in FIGS. 2 and 3) varies in shape andstructure and bears different amounts of pressure in different regionsduring different stages of a gait cycle, to provide support and comfortto the user throughout the gait cycle, the zones 200, 204, 208, 212,216, 220, 224 of the lattice 108 also vary in shape and structure.Additionally, the height H (shown in FIG. 4) of the lattice 108 and/orthe girths 152 (shown in FIG. 6) of the laths 136 and incomplete laths176 differ between the different zones 200, 204, 208, 212, 216, 220, 224of the lattice 108. The height H (shown in FIG. 4) is expressible as atypical scale measurement (i.e., 4 millimeters) and is also expressibleas the number of cell units 156 (shown in FIG. 7) stacked on top of oneanother. By way of example, laths 136 (shown in FIG. 6) and incompletelaths 176 (shown in FIGS. 9A-9C) located within the longitudinal archzone 212 have girths 152 (shown in FIG. 6) that differ from the girths152 of laths 136 and incomplete laths 176 located within the ball of thefoot zone 220. The heights H (shown in FIG. 4) and girths 152 (shown inFIG. 6) of laths 136 and incomplete laths 176 within the transition area228 are gradations between adjacent zones 200, 204, 208, 212, 216, 220,224 to form smooth transitions of heights H (shown in FIG. 4) of thelattice 108 and girths 152 (shown in FIG. 6) of the laths 136 andincomplete laths 176 between the zones 200, 204, 208, 212, 216, 220,224.

Higher heights H provide more material in the lattice 108 extending fromthe second surface 116 of the platform 104 which can be compressed bythe foot 50 (shown in FIGS. 2 and 3) as the user applies pressure duringthe gait cycle. Conversely, lower heights H provide less padding andposition the foot 50 closer to the ground. A gradual decrease in theheight H of the lattice 108 from the heel portion 120 to the toe portion124 of the platform 104 promotes natural rolling from the heel 54 to thetoes 56 of the foot 50 during gait. Thicker girths 152 provide stiffermaterial in the lattice 108 which is less compressible and less springywhen compressed by the foot 50 (shown in FIGS. 2 and 3) as the userapplies pressure during the gait cycle. This is useful, for example, forproviding stability and maintaining structure under the appliedpressure. Conversely, thinner girths 152 provide softer material in thelattice 108 which is more compressible and springier when compressed bythe foot 50 as the user applies pressure during the gait cycle. This isuseful, for example, for providing spring when the user pushes off orremoves pressure and for deforming to better absorb impact. Varyingcombinations of height H and girth 152 result in various amounts ofpadding, compressibility, softness, and stiffness which are appropriatefor accommodating the foot 50 (shown in FIGS. 2 and 3) in the differentzones 200, 204, 208, 212, 216, 220, 224 of the lattice 108 duringdifferent stages of the gait cycle.

More specifically, in the perimeter zone 200, the lattice 108 has avarying height H and laths 136 and incomplete laths 176 with relativelythick girths 152. The height H of the lattice 108 is higher at the heelportion 120 and lower at the toe portion 124 to promote natural rollingfrom the heel 54 to the toes 56 of the foot 50. The relatively thickgirths 152 provide extra support to the outside of the user's foot 50 tokeep the foot 50 aligned with the midsole 100. The laths 136 andincomplete laths 176 in the perimeter zone 200 have girths 152 in arange of, for example, approximately 4.5 to 5.5 millimeters.

In the calcaneus zone 204, the lattice 108 has a relatively high heightH and laths 136 and incomplete laths 176 with relatively thick girths152 to provide substantial padding with relatively stiff cushion to thecalcaneus bone 68. This is useful to pad the calcaneus region 66 of thefoot 50 when a user initially makes contact with the ground during gaitbecause a force of the impact on the calcaneus bone 68 can be quite highduring that event. The calcaneus zone 204 also should not be too soft sothat the lattice 108 does not compress completely under the high force.The height H of the lattice 108 is, for example, two complete cell units156 stacked on top of one another, or approximately 19 millimeters.

In the talus zone 208, the lattice 108 has a relatively high height Hand laths 136 and incomplete laths 176 with relatively thin girths 152to provide substantial padding with relatively soft cushion to the talusregion 70 of the foot 50 during gait. The height H of the lattice 108 inthe talus zone 208 is less than the height H of the lattice 108 in thecalcaneus zone 204 to promote natural rolling from the heel 54 to thetoes 56 of the foot 50. The height H is still sufficiently high toprovide substantial cushion near the high force. The girths 152 are thinenough to provide softer cushioning and springiness as the user pushesoff the heel 54 and begins to roll the foot 50 toward the arch 58. Thelaths 136 and incomplete laths 176 in the talus zone 208 have girths 152of, for example, approximately 3 millimeters.

In the longitudinal arch zone 212, the lattice 108 has a moderate heightH and laths 136 and incomplete laths 176 with relatively thick girths152 to provide some padding with stiffer support to the longitudinalarch region 74 of the foot 50 during gait to reduce collapse of the arch58 of the foot 50 as the user bears weight on the arch 58. The height Hof the lattice 108 in the longitudinal arch zone 212 is, for example,slightly more than one cell unit 156 or approximately 14 millimeters.The laths 136 and incomplete laths 176 in the longitudinal arch zone 212have girths 152 in a range of, for example, approximately 4.5 to 5.5millimeters.

In the metatarsal zone 216, the lattice 108 has a moderate height H andlaths 136 and incomplete laths 176 with moderately thick girths 152 toprovide some padding with some support to the metatarsal region 82 ofthe foot 50 during gait. The height H of the lattice 108 in themetatarsal zone 216 is, for example, slightly less than the height H ofthe lattice 108 in the longitudinal arch zone 212 to promote naturalrolling from the heel 54 to the toes 56 of the foot 50. The laths 136and incomplete laths 176 in the metatarsal zone 216 have girths 152, forexample, slightly thinner than the girths 152 of the laths 136 andincomplete laths 176 in the longitudinal arch zone 212.

In the ball of the foot zone 220, the lattice 108 has a relatively lowheight H and laths 136 and incomplete laths 176 with relatively thingirths 152 to provide relatively little padding with relatively softcushion and relatively high springiness to the ball of the foot region86 of the foot 50 during gait. The relatively low height H, compared tozones nearer to the heel portion 120 of the platform 104, promotesnatural rolling from the heel 54 to the toes 56 of the foot 50 duringthe stages of gait by naturally guiding the foot 50 along a downwardangle from the heel portion 120 toward the toe portion 124 of theplatform 104. Additionally, the relatively low height H of the lattice108 in the ball of the foot zone 220 provide less cushion than otherzones because the ball of the foot region 86 of the foot 50 is naturallymore padded than surrounding regions of the foot 50 and thus includesnatural cushion to be compressed by the foot 50 during gait. The heightH of the lattice 108 in the ball of the foot zone 220 is, for example,approximately 9 millimeters. The relatively thin girths 152 providespringiness as the user begins to push off the foot 50 during gait. Thelaths 136 and incomplete laths 176 in the ball of the foot zone 220 havegirths 152 of, for example, approximately 3 millimeters.

In the toe zone 224, the lattice 108 has low height H and laths 136 andincomplete laths 176 with relatively thick girths 152 to provide littlecushion and enough stiffness for the user to push off of during gait.The low height H promotes natural rolling toward the toes 56 of the foot50 at the end of a gait cycle. The height H is sufficient to providestructure for the user to push off of at the end of a gait cycle. Theheight H of the lattice 108 in the toe zone 224 is in a range of, forexample, approximately 3 to 5 millimeters. The relatively thick girths152 also provide sufficient structure for the user to push off of at theend of a gait cycle. The laths 136 and incomplete laths 176 in the toezone 224 have girths 152 of, for example, approximately 4.5 millimeters.

The arrangement of laths 136 and incomplete laths 176 and cell units 156and incomplete cell units 184 within the zones 200, 204, 208, 212, 216,220, 224 of the lattice 108 provide a midsole 100 that is able to beincluded in a shoe to provide comfort and utility for a user byaccommodating the foot 50 during all stages of the gait cycle. Thelattice 108 enables the midsole 100 to provide mechanical cushioning bydeforming along the structure of the lattice 108, rather than justcompressing, under the weight and applied pressure of the user. Further,the lattice 108 enables the midsole 100 to provide various types andamounts of cushioning to the various regions of the foot 50 due todifferences in height H and girth 152 across the different zones 200,204, 208, 212, 216, 220, 224 of the lattice 108. Accordingly, themidsole 100 provides three-dimensional zonal compression to a userduring all stages of the gait cycle.

As shown in FIG. 10, in at least one exemplary embodiment, the midsole100 is configured to be inserted into an outsole 300. By forming themidsole 100 as a single, unitary piece capable of being inserted intothe outsole 300, it is possible to produce customized shoes. In theexemplary embodiment shown in FIG. 10, the midsole 100 fits tightlywithin the outsole 300 such that the lattice 108 is visible throughopenings 304 formed in the outsole 300. The openings 304 provide visualaccess to the midsole 100 from outside the customized shoe.

As mentioned above, the platform 104 and the lattice 108 are integrallyformed, and the lattice 108 is formed as a single, unitary piece.Accordingly, the entire midsole 100 is formed as a single, unitarypiece. As used herein, the term “single, unitary piece” is intended tomean an indivisible part that is not joined together after being formedand cannot be disassembled without destruction of the part. To form thethree-dimensional structure of the midsole 100, including the opencrisscrossing structure of the lattice 108, as a single, unitary piecemust be accomplished using a highly capable manufacturing technique.More specifically, the midsole 100 is not formed using injection moldingprocesses and the midsole 100 does not include any indications ofinjection molding processes, including gate marks, sprue marks, partingline marks, and ejector pin marks. In this exemplary embodiment, themidsole 100 is formed using three-dimensional printing or selectivelaser sintering processes.

As is known in the art, three-dimensional printing and selective lasersintering processes are known as “additive processes” because theyinclude progressively adding material to form the product. This is incontrast to manufacturing processes that start with a larger piece andprogressively remove material to form the product. As shown in FIG. 11,the midsole 100 is formed using process 400. To form the midsole 100using three-dimensional printing and selective laser sinteringprocesses, the platform 104 and the lattice 108 are printed such thatthe first surface 112 of the platform 104 conforms to the foot 50 of theuser (step 402) and the lattice 108 extends from the second surface 116of the platform (step 404). Printing the lattice 108 includes printingthe laths 136 and the incomplete laths 176 joined together at vertices164 and incomplete vertices 180 to form cell units 156 and incompletecell units 184. In at least one exemplary embodiment, the steps of theprocess are performed in reverse order. In at least one exemplaryembodiment, the steps of the process are performed simultaneously.

By forming the midsole 100 with three-dimensional printing and selectivelaser sintering processes it is possible to form complexthree-dimensional structures including undercuts and patterns of throughholes, such as the crisscrossing structure of the lattice 108.Additionally, the lattice 108 and the platform 104 can be integrallyformed of the same material in the same processing step. Because themidsole 100 is a single, unitary piece, the comfort and utility providedto the user can be accomplished with one piece instead of many.Accordingly, it is possible that the midsole 100 is less expensive toproduce than a larger number of parts to be combined together toaccomplish the same objective as the midsole 100.

In at least one exemplary embodiment, the midsole 100 is specificallyconfigured to conform to a particular user's foot. As shown in FIG. 12,the midsole 100 of this exemplary embodiment is formed using a process500. More specifically, measurements of a user's foot are taken (step502), including shape and size as well as force and pressuredistributions along the bottom of the foot during the stages of variousgait cycles. These measurements are used to prepare a pattern for acomplementary lattice 108 (step 504) with properties of the zones 200,204, 208, 212, 216, 220, 224 and properties of the laths 136 andincomplete laths 176 and cell units 156 and incomplete cell units 184within the zones 200, 204, 208, 212, 216, 220, 224 determined by theuser's individual characteristics. By way of example, if the userapplies a great amount of pressure to the heel 54 of the foot 50 duringinitial contact with the ground during a gait cycle, the height H of thelattice 108 in the calcaneus zone 204 is increased to provide additionalcushion. Similarly, by way of example, if the user's arch 58 tends tocollapse inwardly while the user applies pressure during the gait cycle,the girths 152 of the laths 136 and incomplete laths 176 in thelongitudinal arch zone 212 are increased to provide additional supportand reduce compression. In this way, the midsole 100 is customizable andcan be configured to provide custom support to the various regions ofthe foot 50 through each of the zones 200, 204, 208, 212, 216, 220, 224.Next the midsole 100 is formed using three-dimensional printing andselective laser sintering processes, the platform 104 and the lattice108 are printed such that the first surface 112 of the platform 104conforms to the foot 50 of the user (step 506) and the lattice 108extends from the second surface 116 of the platform (step 508). Printingthe lattice 108 includes printing the laths 136 and the incomplete laths176 joined together at vertices 164 and incomplete vertices 180 to formcell units 156 and incomplete cell units 184. In at least one exemplaryembodiment, steps 506 and 508 of the process are performed in reverseorder. In at least one exemplary embodiment, steps 506 and 508 of theprocess are performed simultaneously.

What is claimed is:
 1. An article of footwear comprising: an upper; amonolithic midsole connected to the upper, the monolithic midsoleincluding: a platform extending along a perimeter portion of themidsole; and a lattice structure integrally formed with the platform andextending between a toe portion and a heel portion of the midsole, thelattice structure including a network of laths forming a plurality ofoctahedron cell units defining eight faces, each cell unit comprising afirst substantially cylindrical lath directly joined to a secondsubstantially cylindrical lath at a vertex; and an outsole connected tothe midsole.
 2. The article of footwear of claim 1, wherein the platformcomprises a toe portion, a heel portion, and a medial portion, theplatform having a first surface configured to face a sole of a foot of awearer and a second surface opposite the first surface.
 3. The articleof footwear of claim 1, wherein the lattice structure extends from asurface of the platform, the network of laths forming a plurality ofuniform cell units and a plurality of non-uniform partial cell units,each lath of the network of laths having a longitudinal structure with alongitudinal axis and two ends.
 4. The article of footwear of claim 1wherein the network of laths include a plurality of uniform cell unitsand a plurality of non-uniform partial cell units, wherein each cellunit of the plurality of uniform cell units is defined by a plurality offaces, wherein each face of the plurality of faces is defined by an areawithin a plane formed by a plurality of adjacent vertices, wherein eachvertex of the plurality of adjacent vertices is formed by an end of anumber of the laths of the network of laths joined together, and whereinall cell units of the plurality of uniform cell units have asubstantially uniform volume.
 5. The article of footwear of claim 4wherein each non-uniform partial cell unit is defined by at least twopartial faces, each partial face of the at least two partial faces isdefined by an area within a plane formed by at least one vertex and atleast a portion of two laths of the network of laths joined together atthe at least one vertex.
 6. The article of footwear of claim 1 whereinthe network of laths are positioned in at least a first zone and asecond zone, wherein each lath in the first zone has a girth that issubstantially different from a girth of each lath in the second zone. 7.The article of footwear of claim 1, wherein the network of laths includea plurality of regular octahedron cell units, and wherein each vertex isdefined at an angle of said regular octahedron, and wherein eachoctahedron cell unit includes a third substantially cylindrical laththat intersects a fourth substantially cylindrical lath at the vertex.8. The article of footwear of claim 1, wherein the lattice structure isformed as a single unitary part.
 9. The article of footwear of claim 1,wherein the lattice structure is integrally formed with the platformwithout gate marks, sprue marks, parting line marks and ejector pinmarks.
 10. The article of footwear of claim 1 wherein the network oflaths form a plurality of adjacent cell units, the platform connected toa first set of adjacent cell units positioned along an edge of thelattice structure and a second set of adjacent cell units not positionedalong an edge of the lattice structure.
 11. The article of footwear ofclaim 10 wherein the lattice structure includes a plurality of layerssuch that the adjacent cell units include cell units located in a samelayer and cell units located in different layers, wherein the pluralityof layers of the lattice structure extend from a toe portion to a heelportion of the article of footwear.
 12. An article of footwearcomprising: an upper; a midsole connected to the upper, the midsoleincluding a monolithic lattice structure extending from a midfootportion to a heel end of the article of footwear, the monolithic latticestructure including a network of laths forming a plurality of octahedroncell units, each lath of the network of laths having a longitudinalstructure defining a longitudinal axis and two ends, each lath of thenetwork of laths directly joined to another lath at a vertex, theplurality of cell units including complete cell units and incompletecell units; and an outsole connected to the midsole.
 13. The article offootwear of claim 12 wherein each complete cell unit is defined by aplurality of faces, wherein each face of the plurality of faces isdefined by an area within a plane formed by a plurality of adjacentvertices, wherein each vertex of the plurality of adjacent vertices isformed by an end of a number of laths of the network of laths joinedtogether, and wherein all complete cell units have a substantiallyuniform volume.
 14. The article of footwear of claim 13 wherein eachincomplete cell unit is defined by at least two partial faces, whereineach partial face of the at least two partial faces is defined by anarea within a plane formed by at least one vertex and at least a portionof two laths of the network of laths joined together at the at least onevertex.
 15. The article of footwear of claim 12 further comprising aplatform extending along a perimeter portion of the lattice structure,the lattice structure integrally formed with the platform such thatmidsole is monolithic and includes both the lattice structure and theplatform.
 16. The article of footwear of claim 12 wherein the network oflaths are positioned in at least a first zone and a second zone, whereineach lath in the first zone has a girth that is substantially differentfrom a girth of each lath in the second zone.
 17. The article offootwear of claim 12 wherein the network of laths include a plurality ofregular octahedron cell units.
 18. The article of footwear of claim 12,wherein the lattice structure is formed as a single unitary part. 19.The article of footwear of claim 12 wherein the incomplete cell unitsare arranged at an edge of the lattice structure.
 20. The article offootwear of claim 12 wherein the incomplete cell units are arranged in aheel region of the midsole.
 21. An article of footwear comprising: anupper; a monolithic midsole connected to the upper, the midsoleincluding a lattice structure extending between a toe portion and a heelportion of the article of footwear, the lattice structure including anetwork of substantially cylindrical laths forming a plurality ofoctahedron cell units, each of the plurality of octahedron cell unitsdefining eight faces with each face substantially shaped as equilateraltriangle, and each of the substantially cylindrical laths directlyjoined to another substantially cylindrical lath at a vertex; and anoutsole connected to the midsole.
 22. The article of footwear of claim21 wherein each face of the eight faces is defined by an area within aplane formed by at least two laths of the network of laths joinedtogether at a vertex.
 23. The article of footwear of claim 21 whereinthe network of laths are positioned in at least a first zone and asecond zone, wherein each lath in the first zone has a girth that issubstantially different from a girth of each lath in the second zone.24. The article of footwear of claim 21, wherein the lattice structureis formed as a single unitary part.